HRV for wet room exhaust: Will I have to build a motorized damper box myself?
I currently own a 2006 Lifebreath HRV 155cfm unit in SouthWestern Ontario. It was ducted well enough, but it basically pulls from too many areas of the house (kitchen, laundry room, 3 bathrooms). It does a good job of whole house ventilation, but basically it feels underpowered for wet room exhaust (1850sqft 2 story, with unit in basement, so some runs are also quite long, all flex).
In order to “fix” this, I had to adjust the room diffusers to prioritize the ensuite bathroom. I basically shut down all the other diffusers except that one. Steam evacuation is now adequate, but still not stellar.
I am now planning a new house, and the unit I am looking at (Enerboss airhandler/HRV combo) now has a dedicated wet room exhaust port with additional fan, which should help a lot. I would like to take it a step further, and build a junction box going to all 3 bathrooms, with a motorized damper set so when the specific boost switch in a bathroom is triggered, it not only starts the boost fan, but shuts off access to the other 2 bathrooms to give me the full 160cfm to the bathroom being used. Did someone already figure this out (can I buy this pre-made) or will I have to build it myself?
Other details that I hope will help:
Metal ducting for the HRV, as much as feasible
Better positioning of the HRV exhaust in bathrooms (ie in showers vs in bathroom currently)
Walk in showers with a “sealed” design (current glass shower has walls that do not go to the ceiling, with a 1 foot opening at the top that leaks massive amounts of moisture in the bathroom during a shower.)
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